Question

One gallon of gasoline in an automobile's engine produces on the average \(9.5 \mathrm{~kg}\) of carbon dioxide, which is a greenhouse gas; that is, it promotes the warming of Earth's atmosphere. Calculate the annual production of carbon dioxide in kilograms if there are 40 million cars in the United States and each car covers a distance of \(5000 \mathrm{mi}\) at a consumption rate of 20 miles per gallon.

Short answer

The annual production of carbon dioxide is 95 billion kilograms.

Step-by-step solution

Calculate Total Gasoline Consumption

First, determine the average amount of gasoline consumed per car over one year. If each car covers 5000 miles and the consumption rate is 20 miles per gallon, the total gallons of gasoline consumed by one car is given by:\[\text{Total gallons per car} = \frac{5000 \text{ miles}}{20 \text{ miles/gallon}} = 250 \text{ gallons}\]

Calculate Total CO2 Produced by One Car

Next, calculate the total carbon dioxide produced by one car. Knowing that one gallon produces 9.5 kg of carbon dioxide, the total CO2 emissions for one car is:\[\text{CO2 per car} = 250 \text{ gallons} \times 9.5 \text{ kg/gallon} = 2375 \text{ kg}\]

Calculate Total CO2 for All Cars

Finally, multiply the CO2 emissions from one car by the total number of cars (40 million) to find the total annual production of CO2:\[\text{Total CO2 for all cars} = 2375 \text{ kg/car} \times 40,000,000 \text{ cars} = 95,000,000,000 \text{ kg}\]

Key concepts

Greenhouse Gases

Greenhouse gases are a big part of global climate discussions. One well-known greenhouse gas is carbon dioxide (CO2). When gasoline in a car engine burns, it releases CO2 into the atmosphere. CO2 traps heat from the sun, similar to the glass walls of a greenhouse. This heat trapping leads to the warming of the Earth's atmosphere, contributing to climate change. Essentially, the more CO2 and other greenhouse gases there are in the atmosphere, the warmer the planet becomes. This warming can affect weather patterns, sea levels, and wildlife habitats. So, understanding CO2 emissions from cars — a major contributor to greenhouse gases — is crucial for making informed decisions about reducing our carbon footprint.

Fuel Consumption

Fuel consumption is how much fuel a vehicle uses to travel a certain distance. It's typically measured in miles per gallon (mpg) or liters per 100 kilometers in other countries. In this exercise, each car uses 1 gallon of gasoline to travel 20 miles. This is a common way to measure a car's efficiency. If a car has higher fuel consumption, it means it uses more fuel to travel the same distance and emits more CO2. Therefore, choosing vehicles with better fuel efficiency can help reduce overall fuel consumption and cut CO2 emissions. Reducing fuel consumption is not only environmentally friendly but can also save money on fuel costs.

Automobile Emissions

Automobile emissions refer to the gases released when vehicles burn fuel. These include CO2, nitrogen oxides, and hydrocarbons. CO2 emissions from cars are significant due to the sheer number of vehicles on the road. As seen in the exercise, if one car emits 2375 kg of CO2 annually, then 40 million cars result in a staggering 95 billion kg of CO2 per year in the United States alone. These emissions contribute to air pollution and global warming, making it crucial to regulate and reduce emissions from vehicles. Governments and manufacturers are working to produce cleaner technologies like electric and hybrid cars to tackle this problem.

Mileage Calculation

Mileage calculation helps determine the distance a vehicle can travel per unit of fuel. In this exercise, the calculation involves dividing the total miles a car travels by its fuel efficiency in miles per gallon. For example, with a mileage of 5000 miles annually and a fuel efficiency of 20 mpg, the fuel consumption per car is 250 gallons a year. Mileage calculations can help drivers plan fuel stops, assess fuel-related costs, and ensure efficient trips. Improving mileage by maintaining a vehicle, choosing the right tire pressure, and driving conservatively can lead to less fuel consumption and fewer emissions.